Self-centering holder for testing-machines.



W. (I. LOVELAND.

SELF GENTERING HOLDER FOR TESTING MACHINES.

. APPLICATION FILED MAY 6, 19 14.

Patented Dec. 29, 1914.

k/F INVENTOR I MILOmg/mm,

WILLIAJMI J. LOVEIJAND, 01E PITTSBURGH, PENNSYLV in icense.

Specification of Letters Patent.

SELF-CENTJERING HOLDER FOR TESTING-MACHINES.

Patented Dec. 29, 191%.

Application filed May 6, 1914. Serial No. 836,764.

To all whom it may concern:

Be it known that I, WILLIAM J. LOVELAND, a citizen of the United Statesof America, residing at Pittsburgh, in the county of'Allegheny and Stateof Pennsylvania, have invented certain new and useful Improvements inSelf-Centering Holders for Testlug-Machines, of which the following is aspecification, reference being had therein tothe accompanying drawing.

This invention relates to self centering holders for testing machines,and has for its object to provide a device of such class, in a manner ashereinafter set forth, to overcome the objections heretofore existing inholders now in g neral use, one of such objections being the c nstantbreaking of the coupling head for the specimen during the testingoperation,and another of the objections being the stripping of thethreads of the coupling head, under such conditions damaging the head tosuclt an extent as to prevent further use of the same.

A further object of the invention is to provide a specimen holder fortesting machines including a coupling head for the specimen having meanswhereby the more pull upon a pair of oppositely disposed heads, thetighter the ends of the specimen will be secured to the heads, undersuch conditions preventing the separating ofthe ends of the specimenbeing tested from the coupling ends.

Further objects of the invention are to provide a self centeringspecimen holder for testing machines, which is simple in itsconstruction and arrangement, unusually strong, durable, eiiicient inits use, conveniently set up and inexpensive.

With the foregoing and other objects in view, the invention consists ofthe novel construction, combination and arran ement of parts ashereinafter more spec cally described and illustrated in theaccompanying drawings, wherein is shown an embodiment of the invention,but it is to be understood that changes, variations and modificationscan-be resorted to which come within the scope of the, claims hereuntoappended. I I

In the drawings wherein like reference characters denote correspondingparts throughout the several views :Figure 1 is a top plan view of apair of specimen hold-. ers in accordance with this invention, showingthe adaptation thereof in connection with a specimen and with themachine, Fig.

2 is a vertical sectional view of a coupling head showing one end of aspecimen connected therewith, Fig. 3 is a perspective view of one of thesections of the retaining member, Fi 4 is a vertical sectional view of amodified orm of coupling head, Fig. 5 is a perspective of one section ofthe form of retaining member employed in the construction shown in Fig.4, Fig. 6 is a vertical sectional view of another modified formofcoupling head showing the adaptation therewith of one end of a specimen,and Fig. 7 is a perspective view of one of the sections of a form ofretaining member employed in the construction shown in Fig. 6.

Referring to the drawings in detail, 8 and 9 denote the supportingelements of a testing machine to which a pair of self centering specimenholders are connected through the medium of a pair of oppositelydisposed tapering plugs 10 and 11, each provided with a longitudinallyextending bore 12,

- which gradually increases in diameter from its outer toward its innerend, and through the bores 12 are adapted to extend the body portions 13of a pair of oppositely disposed self centering specimen holders. Thebody portion 13 of a holder consists of an elongated cylindrical body,having a reduced peripherally threaded inner end 14 and having its outerend provided with a head 15, which slightly extends into the outer endof the tapered plug. The supporting elements 8 and 9, plugs 10 and 11and the body portion 13 are of known construction and upon the reducedinner end 14 of a body port on is adapted to be secured a coupling head1n accordance with this invention.

The form of coupling head shown in Figs. 2 and 3 consists of a plate 15,formed with a tapered opening 16, the latter gradually increasing indiameter from its outer toward its inner end. Formed integral $W1tl1said plate 15*, at each end thereof, is an arm 17, and the said arms 17terminate 1n a cap 1 8, provided with a centrally disposed openinghaving the wall thereof threaded as at 19 for engagement with theperipherally threaded v 1'8 1.05

removed from the inner end of'the section and merges into asemi-circular groove 22, which gradually tapers toward the inner end ofthe section and the said grooves 21,

, when the sections are positioned in the opening 16 provide a circularopening for the reception of the cylindrical'portion 23 of the end of aspecimen 24. When the sections 19 and 20 are in position in the opening16, the grooves 22 provide a tapering opening for the reception of thetapered portion 25 of the end of the s ecimen 24. p It is obvious f i'omthe foregoing construction-that the greater pull uponthe coupling head,the tighter the end of the specimen 24 will be secured to the couplinghead, in view of the fact that a wedging action is set up between theretaining member and-the wall of the opening 16, and a wedging action isset up between the tapered portion 25 of the end of the specimen 24, andthe wall of the opening formed by the grooves 22. Referring to the formof coupling head shown in Figs. 4 and 5, the difference between the sameand that shown in Figs. 2 and 3, resides in the retaining member, andthe reference characters used in connection with Figs. 2 and 3, with theexception of those employed to designate the retaining member and thespecimen in Figs. 2 and 3, are used to designate the coupling headillustrated in Figs. 4 and 5. The retaining member illustrated in Figs.4 and 5, and which is seated in the openings 16 of the plate 15 consistsof two sections 26 and 27, and the body portion of each of said sectionsis semi-cylindrical in cross section. The body portion of each of saidsections isindicated at 28 and has its outer face 29 thereof taperedfrom its outer toward its inner end.- The body portion 28 is formedintegral with a rectangular cap piece 30, the latter having its inneredge 31 flush with the inner face of the body portion 28. The said bodyportion 28 merges into said cap piece 30. The inner edge 31 of the cappieces 30, centrally thereof, is formed with a semi-circular groove 32,and the inner part of the body portion 28 is formed with a semicirculargroove 33 of the same size of the groove 32, and which merges into saidgroove 32 and the inner face of the body portion 38 is furthermoreprovided with a semi-circular groove 34 of less size than the groove 33,thereby providing a shoulder 35.

The sections of the retaining membei 'are adapted to abut and wheninysiich position the body portions 28 form 'aitapered plug which isseated in the opening .16. and bears against the tapered wall of theopening 16. When. the sections 5f the retaining member are in abuttingposition. the grooves 32 33 and 34 of one body portion 28 register withthe groove 32, 33 and 34 of the other body portion and provide a pair ofcircularopenings, one being of greater diameter than the other. Theregistering grooves 32 and 33 formthe opening of greater diameter. Theopening formed at the grooves 34 are adapted to receive the cylindricalportion 36 of thespecimen 37 and the opening formed by the grooves 32and 33 are adapted to receive the head 38 of the end of the specimen 37,the latter bears against the seat 35 as illustrated in Fig. 4. From theconstruction and arrangement of elements as illustrated in Fig. 4, it isobvious that the more the pull upon the specimen 37, the tighter theretaining member will be secured to the plate 15, due to the wedgingaction between the .39 denotes a plate provided with a centrallydisposed opening 40, which gradually increases in diameter from theouter toward the inner end thereof. Formed integral with the plate 39,at each side thereof, and terminating inwardly with respect to eachof-the plates 39, is an arm 40, and the said arms terminate in a cappiece 41 provided with a centrally disposed opening 42, having the wallthereof threaded for engagement with the reduced threaded inner end 14of the body portion 13. Mounted in' the opening 40, is a retainingmember in the form of a tapered plug, and which is formed of twosections 43 and 44. The body portion of each ofthe sections of theretaining member is indicated at 45, and the inner face of said bodyportion 45 is formed with a semi-circular groove 46, having the wallthereof threaded. The outer face of the section 45 is tapered as at 47.When the sections 43 and 44 are positioned in the opening 40; thetaperedouter faces of said sections bear against the: tapered wall of theopening 40, and under such conditions a wedging action is set up betweenthe re taining member and the wall of the opening 40 when the retainingmember is pulled outwardly with respect to the plate 39. When thesections 43 and 44 are positioned in the opening 40, the grooves 46register and provide a circular opening, and extending in said openingand engaging the threads of the walls of the grooves 46 is aperipherally threaded end 47 of a specimen 48.

By the foregoing arrangement of elements as illustrated in Fig. 6, it isobvious that the more the pull upon the retaining member the tighter itwill engage the plate 39 due to the wedging action between theretainingmember and the wall of the opening 40. r p

By forming the retaining members of two sections, it provides for theconvenient positioning of the ends of the specimens, and furthermore ifone section of a retaining member should become damaged a new one can besubstituted, thus obviating the necessity of casting aside the entireretaining member when formed of one piece and when but one side becomesdamaged.

What I claim is 1. A self centering specimen holder for testing machinescomprising a body portion adapted to be connected with the supportingelement, of a testing machine, a. coupling head comprising a platehaving a tapering opening and further including a pair of outwardlyprojecting spaced armsterminating in a cap detachably secured to saidbody portion, and a tapered retaining member mounted in said opening andprovided with means to receive one end of the specimen to be tested.

2. A self centering specimen holder for testing machines comprising abody portion adapted to be connected with the supporting element of atesting machine, a coupling head comprising a plate having a taperingopening and further including a pair of outwardly projecting spaced armsterminating in a cap detachably secured to said body portion, and atapered retaining member mounted in said opening and provided with meansto receive one end of the specimen to be tested, said retaining memberformed of a pair of complemental sections.

'3. A self centering specimen holder for testing machines comprising abody portion adapted to be connected with the supporting element of atesting machine, a coupling head detachably secured to said body portionand provided with a tapering opening, and a tapering retaining membermounted in said opening and provided with a circular' and a taperedopening, said tapered openingmerging into said circular opening andconstituting means for the reception of one end of the specimen to betested.

4. A self centering specimen holder for testing machines comprising abody portion having a coupling head attached thereto having aplateformed with a tapering opening and further including a pair of outwardlyprojecting spaced arms terminating in a cap detachably secured to saidbody portion, and a retaining member having a wedging engagement in saidopening with said coupling head and provided with means for thereception of one end of the specimen to be tested.

5. A self centering specimen holder for testing machines comprising abody portion having a coupling head attached thereto having a plateformed with a tapering opening and further including a pair of outwardlyprojecting spaced arms terminating in a cap detachably secured to saidbody portion, and a retaining member having a wedging engagement in saidopening with said coupling head and provided with means for thereception of one end of the specimen 7 tthere between and one end of thespecimen to be tested.

7. A self centering specimen holder for testing machines comprising abody portion having a coupling head attached thereto having a plateprovided with a tapered opening and includinga pair of outwardlyprojecting spaced arms terminating in a cap I detachably secured to saidbody portion, a retaining member having a wedging engagement with saidhead and provided with means obtaining a wedging engagement in said bodyportion there between and one end of the specimen to be tested, saidretaining member formed of two sections.

In testimony whereof I aiiix my signature in the presence of twowitnesses.

WILLIAM J. LOVELAND.

Witnesses:

MAX H. SRoLovrrz, L. DUNN.

